lld-link produce broken binaries if /manifestinput:xxx argument is repeated

[alvinhochun]

With this app.manifest:

<?xml version="1.0" encoding="utf-8"?>
<assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1">
<application xmlns="urn:schemas-microsoft-com:asm.v3">
    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
        <ws2:longPathAware>true</ws2:longPathAware>
    </windowsSettings>
</application>
</assembly>

With a simple hello world program manifest_test.cpp:

#include <cstdio>
int main() {
    puts("Hello world");
}

Build:

clang++ -target x86_64-pc-windows-msvc manifest_test.cpp -c -o manifest_test.obj
lld-link -defaultlib:libcmt /OUT:manifest_test.exe /manifest:embed /manifestinput:app.manifest /manifestinput:app.manifest /SUBSYSTEM:CONSOLE /MACHINE:X64 manifest_test.obj

If you try to run the output binary, you will get this error: "The application has failed to start because its side-by-side configuration is incorrect"

Extracting the manifest from the binary using resource hacker gives this:

<?xml version="1.0" encoding="UTF-8"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
  <trustInfo>
    <security>
      <requestedPrivileges>
        <requestedExecutionLevel level="asInvoker" uiAccess="false"/>
      </requestedPrivileges>
    </security>
  </trustInfo>
  <application xmlns="urn:schemas-microsoft-com:asm.v3">
    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
      <ws2:longPathAware>true</ws2:longPathAware>
    </windowsSettings>
    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
      <ws2:longPathAware>true</ws2:longPathAware>
    </windowsSettings>
  </application>
</assembly>

The <windowsSettings> element is duplicated, which I presume is what making Windows unhappy.

Try the same using link.exe instead of lld-link, and the resulting embedded manifest does not have this duplicated element:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1"><trustInfo xmlns="urn:schemas-microsoft-com:asm.v3"><security><requestedPrivileges><requestedExecutionLevel level="asInvoker" uiAccess="false"></requestedExecutionLevel></requestedPrivileges></security></trustInfo><application xmlns="urn:schemas-microsoft-com:asm.v3"><windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings"><ws2:longPathAware>true</ws2:longPathAware></windowsSettings></application></assembly>

[llvmbot]

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